Question

Find the lateral and surface area of each figure. round to the nearest tenth if necessary​

Answer 1

`\large\boxed{7.\ L.A.\approx7771.5\ mm^2}\\\\\boxed{8.\ L.A.\approx621.7\ in^2}\\\\\boxed{9.\ L.A.\approx628\ m^2}`

Explanation:

The formula of a lateral surface of a cone:

`L.S.=\pi rs`

r - radius

s - slant height

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`\pi\approx3.14`

`7.\\r=45mm,\ s=55mm\\\\L.A.=\pi(45)(55)=2475\pi\ mm^2\\\\L.A.\approx2475\cdot3.14=7771.5\ mm^3`

`8.\\r=11\ in,\ s=18\in\\\\L.A.=\pi(11)(18)=198\pi\ in^2\\\\L.A.\approx198\cdot3.14=621.72\ in^2\approx621.7\ in^2`

`9.\\r=10m,\ s=20m\\\\L.A.=\pi(10)(20)=200\pi\ m^2\\\\L.A.\approx200\cdot3.14=628\ in^2`